Nowadays, to detect physiological signals of human body, such as heart beat and brain wave, a plurality of electrode pads of physiological detection equipment is attached to (or worn on) various sites on a surface of human body (also referred to as body surface). These electrode pads detect the current that spreads to the peripheral tissues or body surface occurring when nervous impulses (namely variation of membrane potential) passes through human body organs (such as heart and head). The current is then transmitted by electrical wires to the physiological detection equipment to be converted into data to be displayed. In this way, the condition of an inspected portion (such as heart rate and variation of brain wave) can be realized.
The conventional electrode pad has a structure comprising a base layer (such as a layer of conductive adhesive) and an electrically conductive portion bonded to the base layer. To use in inspecting physiological signals, the body surface (such as skin) is made wet by the stickiness of the base layer or through additional application of a layer of aqueous gel that is electrically conductive in order to help the current on the body surface to flow through the base layer, the electrically conductive portion, and the electrical wires to the physiological detection equipment. On the other hand, to carry out electrotherapy, electrical current is transmitted from the physiological detection equipment to the body surface to penetrate into the body surface to simulate the portion to be treated.
However, the base layer of the conventional electrode pad, as well as the aqueous gel used in combination therewith, is generally not air permeable and may often cause allergy, and thus resulting in uncomfortableness of use. Further, skin chips (for example in condition of dry skin) and grease (in condition of oily skin) are often generated on the human body surface and may easily get stuck to the base layer and interferes with conduction of electrical current. Further, human body has body temperature, which may often causes loss (evaporation) of body surface humidity, or the gel used may get dried and is no longer capable of a humid condition, leading to separation of the adhesive from the base layer. This also interferes with the conduction of electrical current and makes it hard to detect physiological signals. Particularly in a dry condition, the humidity is even harder to keep and interruption of detection results. It may also cause cracking of the base layer.
Further, when multiple conventional electrode pads are used, if these conventional electrode pads are placed too close to each other, then they may get contact with each other and short-circuit may result.
In view of these problems, the present invention aims to provide an improved physiological signal detection device that comprises water-absorbing and wet-keeping electrical pads and is set in engagement with surface of human body to improve electrical conduction for physiological signal detection and to facilitate use in a dry area to detect physiological signals of an inspection subject and to increase convenience of use.